The invention relates to a relay with two contact springs, which each close or interrupt the electric circuit between a first and a second relay contact and whose one end is connected in a conducting fashion with the first relay contact and whose other free end closes or interrupts the electric circuit in a first end position and a second end position of the contact springs, respectively, and with an armature which can be adjusted by means of a magnetic field, whose poles can be changed, for deflecting the contact springs into the respective end position.
A relay of this type is disclosed e.g. in DE 197 15 261 C1.
In this known relay, an electric circuit between two electric relay contacts is closed or interrupted by means of two parallel contact springs. The contact springs are in connection via a displaceable actuator to a permanent magnet of an H-armature which is pivotably retained on two yoke legs of a magnet coil. When the poles of the magnet coil are changed, the permanent magnet is pivoted thereby displacing the actuator. Thereby as the contact springs are grasped behind by the actuator they are deflected from their closed rest position such that the electric circuit is interrupted. The free ends of the contact springs are each biased with force in the direction towards the closed end position by one leaf spring which is mounted to the respective contact spring and is supported with its free end on the actuator.
It is the object of the invention to further develop a relay of the above-mentioned type such that the contact forces acting between the two contact springs and their second relay contacts are as equal as possible and the contact bouncing time of the relay is as minimal as possible.
This object is achieved in accordance with the invention in that a leaf spring is centrally pivotably disposed on the armature or its actuator, whose two free ends bias the two contact springs into the first end position with force.
In the closed relay position, the leaf spring counteracts the deflection of the two contact springs in the opening direction which reduces bouncing when the relay closes. If the contact springs do not close simultaneously, the leaf spring is pivoted by the armature or its actuator towards the lagging contact spring as soon as the leading contact spring abuts its relay contact. Thereby the lagging contact spring is increasingly loaded with force into its closed relay position whereby the closing time is reduced and bouncing is reduced when the lagging contact spring is closed and the contact forces acting between the two contact springs and their second relay contacts are matched. This reduces the bouncing time of the overall relay in total.
The free ends of the leaf spring are preferably arc-shaped in the direction towards the contact springs such that they can slide with minimum friction on the contact springs when the leaf spring is pivoted. In the most simple case, the leaf spring is retained on the armature or actuator in a clamping fashion along a clamping line defining the pivoting axis of the leaf spring.
The leaf spring is preferably formed from electrically conducting material but may also be formed from electrically insulating material e.g. plastic material. In the latter case, two separate electric circuits can be switched.
The two contact springs are formed either in one piece e.g. as U-shaped leaf spring with two parallel free ends or as two separate leaf springs which are either electrically connected or electrically insulated from each other. In the latter case, two separate electric circuits can be switched.
The actuator is preferably disposed to be linearly displaceable approximately in the deflecting direction of the contact springs and is motionally coupled to the free ends of the contact springs. The contact springs are preferably directly coupled with the armature or its actuator in the opening direction of the relay and motionally coupled with the armature or its actuator in the closing direction of the relay via the leaf spring.